Method Of Manufacturing Embedded Water Soluble Film Carrier

ABSTRACT

A water-soluble film (WSF) system comprises at least one active material embedded/entrapped in the film so as to provide precise and desired release of the at least one active material therefrom. The at least one active material includes detergents, enzymes, softeners, perfumes, pesticides, fungicides, active ingredients, dyes, pigments, hazardous chemicals, active agents for cleaning laundry, dishes, floorings, walls, furniture, fluffs, pulp, and combinations thereof. Online and offline processes can be used for the manufacture of multi-layered WSFs with or without liners. The WSFs can be formed in desired shapes to selectively entrap interacting/non-interacting materials and combinations thereof. The process also provides options for the use of a wide range of raw materials, liners such as paper, film, foil, fabric, etc.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is continuation of application Ser. No. 12/905,035filed Oct. 14, 2010 (now U.S. Pat. No. ______), which in turn is adivisional application of application Ser. No. 10/491,951 filed on Apr.7, 2004, which is the national stage application of InternationalApplication No. PCT/IN2002/00202 filed on Oct. 7, 2002 which claims thebenefit of earlier filed Indian Patent Application No. 443/MUM/2001filed on Oct. 9, 2001. All of said applications are incorporated hereinby reference.

FIELD OF INVENTION

This invention relates to a water soluble film (WSF) system withembedded/entrapped water-soluble films (WSF) and a process ofmanufacturing the same. More particularly, the invention relates to aWSF system with actives embedded/entrapped therein such as to provideprecise and desired release of actives therefrom and its method ofmanufacturing for diverse applications, in which a variety of substancessuch as detergents, enzymes, softeners, perfumes, pesticides,fungicides, active ingredients, dyes, pigments, hazardous chemicals,active agents for cleaning laundry, dishes, floorings, walls, furniture,etc., and the like can be so embedded/entrapped for such purpose.

BACKGROUND ART

In various processes/operations and in day-to-day life, a number ofsubstances including hazardous or non-hazardous chemicals are requiredto be delivered in the precisely measured doses.

Attempts by the packaging industry has been to develop approaches toevolve accurate delivery systems for active materials especially thosethat are expensive or are environmentally sensitive or havepossibilities of reacting with other ingredients in formulations. Therehave been several attempts in the past to either encase or laminate orpackage different materials in water-soluble films (WSF).

The objective of delivering precise quantities of products likedetergents has been addressed by the industry for example by packagingdetergents in “soluble” and “non-soluble” sachets in dosages rangingfrom 20 gms/sachet to 50 gms/sachet. In case of non-soluble sachets thedetergents tend to adhere to statically charged packaging materialsurface thereby inhibiting their total transfer to the point ofapplication. Similar problems of particles adhering to staticallycharged surface are faced when small and precise quantities ofpesticides actives are to be packed in non soluble sachets. In the caseof soluble sachets, problems arising out of chemical reaction of theingredients to the film cause serious problems in its smoothapplications. Similarly in the case of pesticide packaging the activeingredients in the package varies from about 2% to about 30% based onthe formulation.

U.S. Pat. No. 4,416,791 discloses a packaging film comprising a basefilm of at least partially water-soluble plastics material carrying onone surface only a protective layer, in particulate form, of an inertplastics material having a contact angle to water of at least 80°degree, the said layer being effective to protect the base film surfacefrom attack by aqueous media. Such a packaging film has the advantagesthat, on its unprotected side, it can be dissolved away, or partlydissolved and partly dispersed, by water, whereas on the side carryingthe protective layer it is protected from attack by aqueous systems andother aggressive media. It is essential that the inert protective layerbe in the form of substantially un-coalesced discrete particles attachedfirmly to the base film but only loosely or not at all to each other, sothat if the base film is dissolved away the protective layer has littleor no integrity and is rapidly dispersed. Further it provides a packagecomprised of the packaging film defined above, having the protectivelayer on its internal surface(s), so that the layer protects the packagefrom attack by any water present inside the package. It is claimed thatsuch a product can be used to package liquid or solid detergent usefulfor dosing into domestic or commercial washing machines.

In one of the methods described in the patent a cold-water-solublepolyvinyl alcohol/polyvinyl acetate film having a thickness of 0.0038 cmwas heated to a temperature just above its glass transition temperatureto render it slightly tacky. Polytetrafluoroethylene powder is sprinkledonto the upper surface of the heated film. The film is then passedbetween rollers heated and then allowed to cool.

The limitation of U.S. Pat. No. 4,416,791 is that it requires a preformed WSF substrate and the extent of coating of thePolytetrafluoroethylene powder would be restricted to the surface of theWSF. By this process it would not be possible to control the depth towhich the Polytetrafluoroethylene powder can be embedded.

The end use of this invention would be limited to the water repellencyand the release properties of Polytetrafluoroethylene powder on thesurface of the pre formed WSF.

U.S. Pat. No. 4,176,079 discloses an invention for dispersing an enzymeinto water soluble resin and forming the resin by casting or extrudinginto a sheet. The sheet is then dried, if necessary, and, if required,cut into “ribbons” for incorporation into the detergent product. Theribbons of enzyme-dispersed resin may be admixed with a detergentcomposition in granular, viscous liquid, paste or gel form. Theresulting mixture may be used directly in the washing process,particularly in an automatic dishwasher, or it may be incorporatedwithin a water-soluble packet, for easy and convenient dispensing. Inthis case the water soluble resin is being used as a means to bind theenzyme to its matrix. This method of preparing the ribbons also suffersfrom the shortcoming that two or more reacting substances cannot bedispersed in the same film as they would interact with each other anddegrade.

U.S. Pat. No. 6,378,274 discloses a process for producing a thermoformedpackage of the type comprising the steps of placing a first sheet offormable film over a forming die having a cavity, molding the film intothe cavity thereby forming a recess in the film, placing a compositionin the thus formed recess, and sealing a second sheet of film across therecess to close the package. In particular, the prior art relates tosuch a process for producing a water-soluble package containing adetergent composition. The disclosure is restricted to thermo-formedpackages formed out of a combination of soluble and insoluble films. Italso needs pre formed films to be operated on offline equipment forpackaging applications thereby making the process of incorporating thematerials within the films very complex and requiring expensiveequipment.

Patent No. EP 0493553 relates to a containerization system and tocontainers which are particularly suitable for storing, packaging andtransporting toxic or hazardous products, such as agriculturalchemicals. The containerization system comprises the chemical in theform of a gel, which is contained within a water soluble orwater-dispersible bag. This EP '553 has limitations as it is restrictedto toxic products that can be converted into gels and then packaging ofgel into a WSF bag.

Patent No. EP 034722081 relates to a package comprising e.g. a liquidchemical or a chemical dissolved or dispersed in an organic liquidcontained in an envelope of water-soluble or water dispersible materialand having a water-soluble or water dispersible seal. The patent alsoprovides a process for the preparation of a package according to theinvention which comprises heat sealing the envelope material to obtain awater dispersible or, preferably, a water soluble heat seal. This priorart specifically discusses packaging of pesticides by means of anefficient heat seal system into a container.

Patent GB 2244258B relates to a package comprising hazardous chemicaldissolved or dispersed in a liquid or gel which is contained in anenvelope of water-soluble or water-dispersible material. The patentseeks to provide a new container system for agrochemicals which is safeto handle. This patent also provides a package which comprises ahazardous chemical dissolved or dispersed in a liquid or gel containedin a water-soluble or water-dispersible laminated film. There is alsodiscussed the delivery of toxic and hazardous materials by means ofplain and laminated soluble sachets.

It would be evident from the above state of the art that none of theprior art teach or provide for delivery of the encased, laminated orpackaged material in precise quantities. It is therefore thelong-standing need of industry to develop efficient and cost effectivestable embedded WSFs for controlled dosing in diverse applications andespecially to embed a wide variety of substances avoiding interactionwith each other within films. Further the need for carriers that canselectively carry combination of materials with dissimilar propertiessuch as miscible/in-miscible, hydrophobic/hydrophilic ingredientscontinues to elude the industry.

OBJECT OF THE INVENTION

The main object of the present invention is to provide stable watersoluble film system having embedded/entrapped actives and to a processfor the manufacture of such stable water soluble films for diverseapplications, in which a variety of substances such as detergents,enzymes, softeners, perfumes, pesticides, fungicides, pigments,hazardous chemicals, active agents for cleaning laundry, dishes,floorings, walls, furniture etc., and the like are embedded/entrappedsingly or in combination for delivering them in precise and desireddosages.

Another object of the present invention is to provide an offline processfor the manufacture of stable water soluble films for diverseapplications, in which a variety of substances such as detergents,enzymes, softeners, perfumes, pesticides, fungicides, pigments,hazardous chemicals, active agents for cleaning laundry, dishes,floorings, walls, furniture etc., and the like are embedded/entrappedsingly or in combination for delivering them in precise and desireddosages.

Another object of the invention is to provide a process of entrappingabsorbent materials such as fluff, pulp and the like within WSFs.

It is yet another object of the invention to disperse diversenon-water-soluble materials on the surface and within WSFs.

Yet another object of the present invention is to provide a process formanufacture of multi-layered WSF to selectively entrapinteracting/non-interacting materials.

Yet another object of the present invention is to provide a process formanufacture of multi-layered WSF to selectively entrap combination ofmaterials with similar and/or dissimilar properties.

It is yet another object of the invention to provide a process ofmanufacturing of WSFs with materials embedded in selective areas of theWSFs in desired shapes.

It is yet another object of the invention to provide WSFs for diverseapplications, in which a variety of substances such as detergents,enzymes, softeners, perfumes, pesticides, fungicides, pigments,hazardous chemicals, active agents for cleaning laundry, dishes,floorings, walls, furniture etc., and the like are embedded fordelivering them in precise and desired quantities.

It is yet another object of the invention to provide a process for themanufacture of WSFs exploiting the various embodiments of the inventionusing a wide range of raw materials including polyvinyl alcoholcopolymer ionomers, polyvinyl alcohol homopolymer, non-ionomeric polyvinyl alcohol polymer, polymethacrylate, polyvinyl alcohol,polyacrylamide, polymethacrylamide, polyacrylic acid, polymethacrylicacid, polyethyleneglycol, polyvinylpyrrolidone, proteinaceous binderssuch as gelatin modified gelatins such as phthaloyl gelatin,polysaccharides, such as starch, gum arabic and dextrin andwater-soluble cellulose derivatives.

It is yet another object of the invention to provide a process for themanufacture of WSFs with the options to use a range of liners such aspaper, film, foil or fabric, preferably of film, more preferably ofpolyester film. The film liners may be plain, metalized, embossed, glossor matte depending upon the desired end product parameters. Paper linercan be plain, embossed, gloss, matte, extrusion coated laminated orrelease coated. Fabrics made of cotton or synthetic yarns, solutioncoated, plain, embossed, gloss, matte, extrusion coated or laminated maybe used as liner dependent upon the desired end product properties.Foils made of steel, aluminum, copper or mixture thereof, morepreferably aluminum foil, plain, embossed, gloss, matte, extrusioncoated laminated or release coated. A liner may be made of a combinationof any or all of the above materials. A liner may be used for single useor may be used for multiple uses.

SUMMARY OF THE INVENTION

Thus according to one aspect of the present invention there is provideda WSF system comprising at least one active material embedded and/orentrapped at selected concentrations and depths/dispositions thereinsuch that said active material thus embedded/entrapped could bedelivered at precisely regulated dosages.

According to another aspect the present invention is directed to aprocess for the manufacture of embedded/entrapped water-soluble film(WSF) system comprising:

-   -   i) providing the formulation of said WSF with or without liner        material;    -   ii) subjecting the said WSF to casting wherein at least one        desired active material is embedded/entrapped prior to and/or        after the said casting of the WSF.

According to another aspect, the present invention is directed to aprocess for the manufacture of embedded/entrapped water-soluble film(WSF) system using a casting liner or a conveyor comprising:

-   -   i) mixing of the formulation of WSF;    -   ii) casting of at least one WSF at least one casting head;    -   iii) metering of the cast film at the respective casting head,        wherein said active material to be embedded is added with the        WSF prior to casting and/or at least during casting;    -   iv) smoothening of the at least one film thus formed; and    -   v) drying of the WSF.

According to another aspect, the present invention is directed to aprocess comprising the steps of dispersing of material to be embedded onsaid cast WSF prior to the step of smoothing at anyone or more of saidcasting heads for casting of the films. The WSF films thus embedded arewound and retained.

According to another aspect, the present invention is directed to aprocess comprising:

-   -   i) unwinding a pre-formed WSF from an unwinder and guiding it        through guide rolls to meet the WSF with said embedded materials        for further entrapping of the materials embedded; followed by    -   ii) guiding the multilayered WSF of step (i) through hot/chill        device for rewinding or splitting.

According to another aspect, the present invention is directed to usinga casting conveyor without liner comprising:

-   -   i) casting of WSF with embedded material the temperature range        maintained from 10° C. to 95° C., preferably 13° C. to 90° C.,        more preferably 15° C. to 85° C.;    -   ii) metering of the cast film at casting head;    -   iii) smoothening of the film with the embedded materials at the        primary station;    -   iv) drying of the WSF from step (i), the temperature range in        the dryers ranging from 50° C. to 250° C., preferably from        60° C. to 200° C., more preferably from 55° C. to 170° C.;    -   v) rewinding of the WSF.

According to yet another aspect, the present invention is directed to aprocess using a Casting WSF on a liner comprising:

-   -   i) providing a liner for the formation of WSF with or without        treating/coating;    -   ii) casting of WSF with embedded material, the temperature range        of the batch solution maintained from 10° C. to 95° C.,        preferably from 13° C. to 90° C., more preferably from 15° C. to        85° C.;    -   iii) metering of the cast film at casting head;    -   iv) smoothening of the film with the embedded material at        primary station, the percentage of solid content maintained in        the range of 3% to 85%, preferably in the range of 4% to 70%,        more preferably in the range of 5% to 65%;    -   v) drying of the WSF, the temperature range in the dryers        maintained from 50° C. to 250° C., preferably from 60° C. to        200° C., more preferably 55° C. to 170° C.;    -   vi) casting of WSF with or without the material to be embedded        at secondary/tertiary subsequent casting head(s);    -   vii) drying of the WSF, the temperature range in the second        dryers maintained from 50° C. to 200′C., preferably 60° C. to        160° C., more preferably 55° C. to 140° C.;    -   viii) guiding the multi-layered WSF through hot/chill device for        rewinding or splitting.

According to a further aspect, the present invention is directed to aprocess using a spraying method comprising:

-   -   i) unwinding of the liner for the formation of WSF and/or a        conveyor is provided;    -   ii) optional coating of the liner via a primer coating station;    -   iii) casting of WSF with material to be embedded at a primary        casting head, the temperature range of the batch solution        maintained from 10° C. to 95° C., preferably 13° C. to 90° C.,        more preferably 15° C. to 85° C.;    -   iv) metering of the cast film at a casting head;    -   v) executing a controlled dosing by spraying of pre-measured        material to be embedded by primary sprayer;    -   vi) smoothening of the film with the embedded material at a        primary station;    -   vii) drying of the WSF at a dryer, the temperature range in the        dryers maintained in the range of 50° C. to 250° C., preferably        from 60° C. to 200° C., more preferably 55° C. to 170° C.;    -   viii) casting of WSF with or without the material to be embedded        at secondary/tertiary subsequent casting head(s);    -   ix) drying of the WSF, the temperature range in the second dryer        maintained 50° C. to 200° C., preferably 60° C. to 160° C., more        preferably 55° C. to 140° C.;    -   x) guiding the multilayered WSF through hot/chill cylinder for        rewinding or splitting.

According to another aspect the present invention is directed to aprocess using a secondary application on partially formed filmcomprising:

-   -   i) unwinding of the liner for the formation of WSF and/or        providing a conveyor;    -   ii) optional coating of the liner via a primer coating station;    -   iii) casting of WSF with material to be embedded at primary        casting head, the temperature range of the batch maintained in        the range of 10° C. to 95° C., preferably 13° C. to 90° C., more        preferably 15° C. to 85° C.;    -   iv) metering of the cast film at casting head;    -   v) smoothening of the film with the embedded material at primary        station, drying of the WSF, the temperature range in the dryers        maintained in the range of 50° C. to 250° C., preferably from        60° C. to 200° C., more preferably 55° C. to 170° C.;    -   vi) executing a controlled dosing by spraying of pre-measured        material to be embedded by secondary disperser;    -   vii) smoothening of the film with the embedded material at a        secondary station;    -   viii) casting of WSF with or without the material to be embedded        at secondary/tertiary subsequent casting head(s);    -   ix) drying of the WSF, the temperature range in the second dryer        is maintained in the range of 50° C. to 200° C., preferably        60° C. to 160° C., more preferably 55° C. to 140° C.;    -   x) guiding the multilayered WSF through hot/chill cylinder for        rewinding or splitting. Optionally offline or online splitting        between the WSF film and the liner.

According to another aspect, the present invention is directed to onlineentrapment comprising:

-   -   i) unwinding of the liner for the formation of WSF and/or        providing a conveyor;    -   ii) optional coating of the liner via a primer coating station;    -   iii) casting of WSF with material to be embedded at primary        casting head, the temperature range maintained 10° C. to 95° C.,        preferably 13° C. to 90° C., more preferably 15° C. to 85° C.;    -   iv) metering of the cast film at casting head;    -   v) smoothening of the film with the embedded material at primary        station;    -   vi) drying of the WSF, the temperature range in the dryers        maintained in the range of 50° C. to 250° C., preferably from        60° C. to 200° C., more preferably from 55° C. to 170° C.;    -   vii) casting of WSF with or without the material to be embedded        at secondary/tertiary subsequent casting head(s);    -   viii) drying of the WSF, the temperature range in the second        dryers maintained from 50° C. to 200° C., preferably 60° C. to        160° C., more preferably 55° C. to 140° C.;    -   ix) unwinding of a pre-formed WSF from an unwinder and guiding        it through the guide rolls to meet the WSF, with embedded        material for entrapping of materials embedded.

Preferably, in the above process of the invention, the materials of theWSF formulation is taken in a batch reactor and mixed intimately toensure complete dissolution in the desired solvent. As would be evidentfrom the above, various possible embodiments of the process can befollowed.

In one of the embodiments of this invention, the materials to beembedded in the WSF are added to the batch solution and mixed thoroughlybefore feeding it to the casting head for further processing. Thematerials that can be taken into the batch mixing are selected fromthose that are water-soluble, sheer insensitive, temperature resistant,like certain agrochemicals, pesticides, insecticides, softeners,surfactants, perfumes for detergent and laundry industry; disinfectants,de-odorizing liquids, etc.

In another embodiment of this invention the materials to be embedded inthe WSF may optionally be introduced in the process at the primary,secondary, tertiary and subsequent sprayers and or at the second orsubsequent casting heads fed from second and/or subsequent batch mixers.

In another embodiment of the present invention the materials to beembedded is dispensed in between incoming cured or uncured WSFs

In another embodiment of the present invention, the process may becarried out with the aid of a self-rolling conveyor.

In yet another embodiment of the present invention, the process may becarried out with the aid of a casting liner.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic drawing showing a system for casting of a watersoluble film on a conveyor;

FIG. 2 is a schematic drawing showing a system for casting of a watersoluble film on a liner;

FIG. 3 schematically shows a vertical method for trapping dispensedmaterial between water soluble films; and

FIG. 4 schematically shows a horizontal method for trapping dispensedmaterial between water soluble films.

DETAILED DESCRIPTION IN RELATION TO ACCOMPANYING FIGURES

The details of the invention its objects and advantages are explainedhereunder in greater details in relation to non-limiting exemplaryillustrations given in FIGS. 1-4

The explanation to the part numbers in FIG. 1 is given below:

1 Conveyor; 2 Guide Roll; 3 Batch Mix; 4 Primary Casting Head; 5 PrimarySprayer; 6 Smoothening Rolls; 7 Dryer; 8 Secondary Sprayer; 9 SecondaryCasting Head; 10 Dryer; 11 Tertiary Sprayer; 12 Disperser forEntrapment; 13 Guide Roll; 14 Chilling Cylinder; 15 Rewinder; 16 GuideRolls; 17 Unwinder; 18 Smoothening Rolls; 19 Batch Mix; 20 Nip Roll;

Accordingly as illustrated in FIG. 1 the process comprises of thefollowing steps:

-   -   1. Batch Mixing of the formulation of WSF and optionally the        material to be embedded;    -   2. Casting of WSF with or without the material to be embedded at        primary casting head;    -   3. Metering of the cast film at casting head;    -   4. Optionally dispersing of material to be embedded by primary        sprayer;    -   5. Smoothening of the film with or without the embedded        materials at the primary station;    -   6. Drying of the WSF from step 2;    -   7. Optional spraying of material to be embedded using a        secondary sprayer;    -   8. Smoothening of the film with or without the embedded        materials at the secondary station;    -   9. Drying of the WSF from step 7;    -   10. Casting of WSF with or without the material to be embedded        at secondary casting head;    -   11. Optional spraying of material to be embedded by a tertiary        disperser;    -   12. Rewinding of the WSF;    -   13. Optionally as a post-step 11 step unwind a pre-formed WSF        from an unwinder and guiding it through the guide rolls to meet        the WSF from step 11 for entrapping of materials to be embedded;    -   14. Guide the multilayered WSF of step 13 through hot/chill        cylinder for rewinding or splitting;

Optionally the steps 1 to 14 may also be carried out on a casting liner(FIG. 1) or a conveyor (FIG. 2).

The invention and the various embodiments are further explainedhereunder in relation to the accompanying figures:

Casting Conveyor without Liner (FIG. 1)

This process comprises of the following:

-   -   1. Casting of WSF on (1) at (4) with embedded material in the        batch mix. The temperature range of the batch solution may vary        from around 10° C. to around 95° C., preferably around 13° C. to        around 90° C., preferably around 15° C. to around 85° C.    -   2. Metering of the cast film at casting head.    -   3. Smoothening of the film with the embedded materials at the        primary station (6).    -   4. Drying of the WSF from step 1 at (7). The temperature range        in the dryers may vary from around 50° C. to around 250° C.,        preferably between around 60° C. to around 200° C., more        preferably between around 55° C. to around 170° C. Rewinding of        the WSF at (15).

Casting WSF on a Liner (FIG. 2)

The explanation to the part numbers in FIG. 2 is given below:

25 Unwinder of “Carrier Web”; 26 Primer Coating; 27 Batch Mix; 28Primary Casting Head; 29 Primary Sprayer; 30 Smoothening Roll; 31 Dryer;32 Secondary Sprayer; 33 Secondary Casting Head; 34 Dryer; 35 TertiarySprayer; 36 Disperser for Entrapment; 37 Guide Roll; 38 ChillingCylinder; 39 Rewinder; 40 Guide Rolls; 41 Unwinder; 42 SmootheningRollers; 43 Batch Mix; 44 Nip Roll;

This process comprises of the following:

-   -   1. Unwinding of the liner at (25) for the formation of WSF which        can be optionally treated or untreated and coated or uncoated.        Liners can be of paper, film, foil or fabric, preferably of        film, more preferably of polyester film. The films can be in the        range of 2 microns to 500 microns, preferably in the range of 10        microns-300 microns, more preferably in the range of 12        microns-250 microns. The film liner may be plain, metallized,        embossed, gloss, matte, extrusion coated laminated or release        coated depending on the desired characteristics of the end        product. The paper Liner is also used for production of WSF        film, Paper liners that accept temperatures needed for        production of WSF, GSM (Grams per sq. meter—the standard for        measuring weight of paper) may be in the range of around 7 gms        to around 500 gms, preferably a range of around 20 gm to around        300 gms, more preferably in the range of around 60 gm to around        180 gms. The paper liner may be plain, embossed, gloss, matte,        extrusion coated laminated or release coated depending on the        desired characteristics of the end product. Fabrics made of        cotton or synthetic yarns, solution coated, plain, embossed,        gloss, matte, extrusion coated or laminated may be used as liner        based on the desired end product properties.    -   2. Optional coating of the liner via a primer coating station        (26).    -   3. Casting of WSF on (25) at (28) with embedded material in the        batch mix. The temperature range of the batch solution may be        around 10° C. to around 95° C., preferably around 13° C. to        around 90° C., more preferably around 15° C. to around 85° C.    -   4. Metering of the cast film at casting head.    -   5. Smoothening of the film by (30) with the embedded material at        primary station.

The percentage of solid content may be in the range of around 3% toaround 85%, preferably in the range of around 4% to around 70%, morepreferably in the range of around 5% to around 65%.

-   -   6. Drying of the WSF from step 3 at (31). The temperature range        in the dryers may be set from around 50° C. to around 250° C.,        preferably from around 60° C. to around 200° C., more preferably        around 55° C. to around 170° C. The temperature range of the        batch solution may vary from around 10° C. to around 95° C.,        preferably around 13° C. to around 90° C., more preferably        around 15° C. to around 85° C.    -   7. Casting of WSF with or without the material to be embedded at        secondary/tertiary subsequent casting head(s) (33).    -   8. Drying of the WSF from step 7 at (34). The temperature range        in the second dryers (34) may be from around 50° C. to around        200° C., preferably around 60° C. to around 160° C., more        preferably around 55° C. to around 140° C.    -   9. The multi-layered WSF of step 8 is guided through hot/chill        cylinder (38) for rewinding or splitting at (39).

Spraying Method (FIG. 2)

This process comprises of the following:

-   -   1. Unwinding of the liner at 25 for the formation of WSF.        Optionally a conveyor can be used.    -   2. Optional coating of the liner via a primer coating station        (26).    -   3. Casting of WSF with material to be embedded at primary        casting head (28). The temperature range of the batch solution        may vary from around 10° C. to around 95° C., preferably around        13° C. to around 90° C., more preferably around 15° C. to around        85° C.    -   4. Metering of the cast film at casting head.    -   5. Spraying of pre-measured material to be embedded by primary        sprayer (29).    -   6. Smoothening of the film with the embedded material at primary        station (30).    -   7. Drying of the WSF from step 5 at dryer (31). The temperature        range in the dryers may be set from 50° C. to around 250° C.,        preferably from around 60° C. to around 200° C., more preferably        around 55° C. to around 170° C.    -   8. Casting of WSF with or without the material to be embedded at        secondary/tertiary subsequent casting head(s) (33).    -   9. Drying of the WSF from step 8 at dryer (34). The temperature        range in the second dryer (34) may be from around 50° C. to        around 200° C., preferably around 60° C. to around 160° C., more        preferably around 55° C. to around 140° C.    -   10. The multilayered WSF of step 8 is guided through hot/chill        cylinder (38) for rewinding or splitting at (39).

Secondary Application on Partially Formed Film (FIG. 2)

This process comprises:

-   -   1. Unwinding of the liner at (25) for the formation of WSF.        Optionally a conveyor can be used.    -   2. Optional coating of the liner via a primer coating station        (26).    -   3. Casting of WSF with material to be embedded at primary        casting head (28). The temperature range of the batch solution        may vary from around 10° C. to around 95° C., preferably around        13° C. to around 90° C., more preferably around 15° C. to around        85° C.    -   4. Metering of the cast film at casting head.    -   5. Smoothening of the film with the embedded material at primary        station (30).    -   6. Drying of the WSF from step 5 at dryer (31). The temperature        range in the dryers may be set from 50° C. to around 250° C.,        preferably from around 60° C. to around 200° C., more preferably        around 55° C. to around 170° C.    -   7. Spraying of pre-measured material to be embedded by secondary        disperser (32).    -   8. Smoothening of the film with the embedded material at        secondary station (42).    -   9. Casting of WSF with or without the material to be embedded at        secondary/tertiary subsequent casting head(s) (33).    -   10. Drying of the WSF from step 9 at dryer (34). The temperature        range in the second dryers (34) may be from around 50° C. to        around 200° C., preferably around 60° C. to around 160° C., more        preferably around 55° C. to around 140° C.    -   11. The multilayered WSF of step 9 is guided through hot/chill        cylinder (38) for rewinding or splitting at (39). Optionally        offline or online splitting between the WSF film and the liner        can be done.

Online Entrapment Method (FIG. 2)

The process comprises of the following:

-   -   1. Unwinding of the liner at (25) for the formation of WSF,        optionally a conveyor can be used.    -   2. Optional coating of the liner via a primer coating station        (26).    -   3. Casting of WSF with material to be embedded at primary        casting head (28). The temperature range of the batch solution        may vary from around 10° C. to around 95° C., preferably around        13° C. to around 90° C., more preferably around 15° C. to around        85° C.    -   4. Metering of the cast film at casting head.    -   5. Smoothening of the film with the embedded material at primary        station (30).    -   6. Drying of the WSF from step 5 at dryer (31). The temperature        range in the dryers may vary from around 50° C. to around 250°        C., preferably from around 60° C. to around 200° C., more        preferably from around 55° C. to around 170° C.    -   7. Casting of WSF with or without the material to be embedded at        secondary/tertiary subsequent casting head(s) (33).    -   8. Drying of the WSF from step 7 at dryer (34). The temperature        range in the second dryers (7) may be from around 50° C. to        around 200° C., preferably around 60° C. to around 160° C., more        preferably around 55° C. to around 140° C.    -   9. Unwinding of a pre-formed WSF from an unwinder (41) and        guiding it through the guide rolls (40) to meet the WSF from        step 8 for entrapping of materials to be embedded. Both the        liners along with WSF film, which may be semi-cured WSF and the        entrapments, may remain in the roll form or sheet form in its        original construction, stripping from casting liner can be done        immediately or after a self-curing aging period ranging from        around 1 hrs. to around 720 hrs., prior to splitting the liners        so as to deliver the final WSF product with entrapped materials.    -   10. If desired the multi-layered WSF of step 9 may be guided        through hot/chill cylinder (38) for rewinding or splitting at        (39). Optionally offline or online splitting between the WSF        film and the liner can be done.

The process described above offers various possibilities for themanufacture of WSFs with entrapped materials either on a liner or aconveyor. Some of the product options the may be exercised are asfollows:

-   -   H/E/H    -   H/E/C    -   H/E/H/E/H . . . n times    -   C/E/C/E/ . . . n times    -   C/E/C/E/C . . . n times    -   C/E/C . . . n times    -   L/UC/E/UH/E . . . n times    -   L/UH/E/UH/E . . . n times    -   L/UC/E/UC/E . . . n times

L/UC/E/H/L/E . . . n times

L/UH/E/H/L/E . . . n times

L/UC/E/C/L/E . . . n times

Where

-   -   U=Uncured; H=Hot Water Soluble Film; C=Cold Water Soluble Film    -   E=Embedded Material; L=Liner

and the value of “n” is decided based on the application of the finalmultilayered embedded WSF.

The above sequence may be repeated in multiple layers as per therequirements of the end use of the multiply embedded WSFs. Further thisprocess also allows the manufacture of multilayered embedded WSF usingcombinations of Cold WSFs and Hot WSFs in various sequences. It alsoprovides the options of using cured/uncured films of CWSFs and HWSFs inany desired sequences.

Dimples or other embossed or patterned designs can be created duringentrapment by using such designed male/female rollers (46, 51 Sheet No.3) or rollers (60, 61 Sheet No. 4). In case of casting on liner method,both the liners along with WSF film, semi-cured WSF and the entrapmentsmay remain in roll form or sheet form in its original construction,stripping from casting liner can be done immediately or after aself-curing aging period ranging from around 1 hr. to around 720 hrs.,prior to splitting the liners so as to deliver the final WSF film withentrapped materials.

Certain materials such as highly alkaline or highly acidic materials mayreact adversely if added in the batch mix process or if sprayed beforethe gelling process or before the film forming process and may thereforenecessitate the use of entrapment method for incorporating suchmaterials. Certain liquids like oil based perfumes, aromas, softeningagents, cleaning agents etc. or solvent based aromas, softening agents,cleaning agents etc. may be entrapped more efficiently with entrapmentmethod disclosed in this invention.

Offline Entrapment Method

The process to incorporate such sensitive materials described abovecomprises of the following:

Vertical Entrapment Method (FIG. 3).

The explanation to the part numbers in FIG. 3 is given below:

45 Unwinder; 46 Affixing Roper; 47 Guide Roll; 48 Disperser for VerticalEntrapment; 49 Guide Roll; 50 Unwinder; 51 Affixing Roller; 52 Rewinder;

-   -   1. Unwinding of the WSF films (45) and (50) with or without        liner.    -   2. Dispensing of the embodiment at (48) in between two affixing        guide rollers (47 & 49).    -   3. Affixing of the WSF films from step 2 at the affixing rollers        (46 & 51).    -   4. Rewinding in roll form or sheet form or fan-fold form.        Optionally the film can be with or without casting liners. The        casting liners can be stripped immediately or after aging period        of around 1 to around 720 hrs. or can be supplied all together        and the end user may be informed to strip the casting liner        before use. The entrapped film can also be slit in ribbons,        tapes, perforated sheets, perforated tapes, perforated ribbons        or cut sheets of any size.

Such a process offers various process and product options such as:

-   -   1. Entrapped material in WSF with or without carrier.    -   2. Entrapped material in WSF in roll form or pouch form.    -   3. Entrapped material in WSF in roll form with perforates.    -   4. Entrapped material in WSF in sheet form with multiple        pouches.    -   5. All above entrapped material in WSF with casting liner for        the consumer to remove immediately or after aging period of        around 1 hr to around 720 hrs.

Some of the product options the may be exercised are as follows:

-   -   H/E/H    -   H/E/C    -   H/E/H/E/H . . . n times    -   C/E/C/E . . . n times    -   C/E/C/E/C . . . n times    -   C/E/C . . . n times    -   L/UC/E/UH/E . . . n times    -   L/UH/E/L/H/E . . . n times    -   L/UC/E/UC/E . . . n times    -   L/UC/E/H/L/E . . . n times    -   L/UH/E/H/L/E . . . n times    -   L/UC/E/C/LIE . . . n times

Where

-   -   U=Uncured; H=Hot Water Soluble Film; C=Cold Water Soluble Film    -   E=Embedded Material; L=Liner

and the value of “n” is decided based on the application of the finalmultilayered embedded WSF.

The above sequence may be repeated in multiple layers as per therequirements of the end use of the multiply-embedded WSFs. Further thisprocess also allows the manufacture of multilayered embedded WSF usingcombinations of Cold WSFs and Hot WSFs in various sequences. It alsoprovides the options of using cured/uncured films of CWSFs and HWSFs inany desired sequences.

Horizontal Entrapment Method (FIG. 4)

The explanation to the part numbers in FIG. 4 is given below:

55 Unwinder; 56 Guide Roll; 57 Disperser for Horizontal Entrapment; 58Guide Roll; 59 Unwinder; 60 Affixing Roller; 61 Affixing Roller; 62Rewinder; 63 Spillage Controller Knife;

-   -   1. Unwinding of the WSF films (59) and (55) with or without        liner.    -   2. Dispensing of the embodiment at (57) in between two affixing        guide rollers (58 & 56).    -   3. Affixing of the WSF films from step 2 at the affixing rollers        (60 & 61).    -   4. Rewinding in roll form or sheet form or fan-fold form.        Optionally the film can be with or without casting liners. The        casting liners can be stripped immediately or after aging period        of around 1 hr to around 720 hrs. or can be supplied all        together and the end user may be informed to strip the casting        liner before use. The entrapped film can also be slit in        ribbons, tapes, perforated sheets, perforated tapes, perforated        ribbons or cut sheets of any size.

Such a process offers various process and product options such as:

-   -   1. Embedded/entrapped material in WSF with or without carrier.    -   2. Embedded/Entrapped material in WSF in roll form or pouch        form.    -   3. Embedded/Entrapped material in WSF in roll form with        perforates.    -   4. Embedded/Entrapped material in WSF in sheet form with        multiple pouches.    -   5. All above Embedded/Entrapped materials in WSF with casting        liner for the end user to remove after aging period of around 1        hr. to around 720 hrs.

In the above options the WSF film may be pre-embedded and used for themanufacture of the above product options.

In yet other embodiment of the invention, materials that are stable inhot water conditions may be introduced into Hot Water Soluble Films(HWSF) and those that are sensitive to cold conditions can beincorporated in Hot or Cold Water Soluble Films (CWSF).

Applications of the Process Options

The invention with various embodiments are now further illustrated witha few non-limiting Examples:

Example I

Embedding of Actives such as Piian Liquid in WSF

Piian is a water dispersible deodorizer which is commercially availablefrom Piian Systems, USA. Piian was added to the pre-mixed WSFformulation batch and stirred for 6 hours. This was followed by a periodof another 6 hours with continuous slow stirring of the solution. Thesolution was then casted on a continuous casting line. It was then driedand split. Several samples of varying compositions were made toincorporate 10% Piian to 90% in WSFs.

The Grammage per Square Meter (GSM) for the Piian incorporated WSFmeasured as per IS1060 is represented as (A).

A reference WSF without the incorporation of Piian was prepared underidentical conditions. The GSM of this reference sample is represented as(B). The Piian loaded in the WSF is therefore A−B=C.

Strips of 10×10 cms were cut from the material WSF loaded with Piian.

Following are the characteristics of the WSF strips loaded with Piian:

Piian Loaded film=30.5 GSM (±½ Gm)

Loading of Piian=5 GSM

Film thickness of Piian loaded WSF=28 microns

GSM of the Reference film without Piian=26 gms. (±1 gm)

Following are test results of reference WSF and Piian loaded WSF:

Tensile Strength of the reference film (kg/cm²) Dir-I = 380.74 TestMethod—ASTM D-883 Dir-II = 382.67 Test Method—ASTM D-883 Young Modulus(kg/mm²) Dir-I = 13.19 Test Method—ASTM D-882 Dir-II = 8. 14 TestMethod—ASTM D-882 Elongation (%) (kg/cm²) Dir-I = 259.27 TestMethod—ASTM D-882 Dir-II = 252.90 Test Method—ASTM D-882 PunctureResistance (Ozs. Inches/Tear Inch) = 270.00 Test Method—IS-1060 TensileStrength of the Piian Load WSF (kg/cm²) Dir-I = 329.5 Test Method—ASTMD-883 Dir-II = 381.1 Test Method—ASTM D-883 Young Modulus (kg/mm²) Dir-I= 7.38 Test Method—ASTM D-882 Dir-II = 11.81 Test Method—ASTM D-882Elongation (%) (kg/cm²) Dir-I = 252.36 Test Method—ASTM D-882 Dir-II =291.50 Test Method—ASTM D-882 Puncture Resistance (Ozs. Inches/TearInch) = 225.00 Test Method—IS-1060 Dissolution in seconds = 86 secs at30 C. Breaking of the film = 3.14 secs at 30 C.

The film properties of the Piian loaded WSF, together with the uniformdispersion of the Piian in the WSF illustrates that Piian can bedelivered in precise quantities by incorporating it in the WSF using theprocess disclosed in the invention.

In one of the variants of the process described in this invention,pre-dissolved enzymes may be mixed in a WSF formulation and a controlledcasting on a preformed substrate/liner based WSF film is possible.Alternatively two pre-formed substrate based WSF films may be used. Awater-based enzyme may be loaded to precisely fill the center of the twofilms. The water based enzyme helps to affix the two films substrates sothat the enzymes are sandwiched in between the films thereby resultingin an enzyme loaded WSF. The two substrates can then be stripped offafter appropriate ageing.

Enzymes in precise quantities can be incorporated in singly ormulti-layered WSFs by the process described in this invention so thatthe processor or the user does not inhale the enzyme. The enzymeembedded WSF can be incorporated into detergent formulations or added towashing medium in a machine or a washing vessel such as a bucket toensure that the precise dosage of enzymes are added at the point ofapplication.

Example II

Incorporation of Large Particles in WSFs

Non-soluble Acrylic resins (72-75 microns) were dispersed into coldwater-based solutions to form a high viscous dispersion. The liquiddispersion was dropped in between two films through a motorized valvecontrolled slot nozzle to have a margin at the end of the webs, therebynot allowing the dispersion to ooze out from the sides. Cold water wasused as the solvent. Both the WSFs used were Hot Water Solubleformulations. In this process the Hot Water Soluble Films. Do not getaffected by cold-water dispersion and therefore remain entrapped tillthe acrylic entrapped film passes through the dried and reaches therewinder. Typically the film is split from its casting liner after anappropriate aging period.

The properties of the acrylic incorporated films were:

Acrylic Loaded GSM=60 GSM (±½ Gm)

Microns of Acrylic loaded film 140 microns

Base films GSM=58 GSM (±1 gm)

Weight of Acrylic Entrapping=2 GSM

Similarly following are test results of reference WSF and Acrylic resinloaded WSF

Tensile Base film (kg/cm²) Dir-I = 380.74 Test Method—ASTM D-883 Dir-II= 382.67 Test Method—ASTM D-883 Young Modulus (kg/mm²) Dir-I = 13.19Test Method—ASTM D-882 Dir-II = 8.14 Test Method—ASTM D-882 Elongation(%) (kg/cm²) Dir-I = 259.27 Test Method—ASTM D-882 Dir-II = 252.90 TestMethod—ASTM D-882 Puncture Resistance Ozs. Inches/Tear Inch) = 270.00Test Method—IS-1060 Tensile Acrylic Entrapped film (kg/cm²) Dir-I =80.69 Test Method—ASTM D-883 Dir-II = 83.46 Test Method—ASTM D-883 YoungModulus (kg/mm²) Dir-I = 2.79 Test Method—ASTM D-882 Dir-II = 3.25 TestMethod—ASTM D-882 Elongation (%) (kg/cm²) Dir-I = 229.5 Test Method—ASTMD-882 Dir-II = 206.7 Test Method—ASTM D-882 Puncture Resistance (Ozs.Inches/Tear Inch) = 180.0 Test Method—IS-1060 Dissolution of film inseconds = 47 secs at 30 C. Breaking of the film = 3.75 secs at 30 C.

The WSF characteristic with the hydrophobic polymer indicates that theprocess disclosed in the invention can be effectively used to embed anyhydrophobic materials of diverse shapes and sizes within a WSF matrix.

Also this application shows the possibility of using two hot watersoluble films or a combination thereof, taking advantage of thehydrophilic properties. This application also shows the advantage ofusing casting liners.

Example III

Films Incorporating Water Insoluble Fine Particles

The performance of the films based on water insoluble fine particleswere prepared by the process described in this invention. Fine particlesized iron oxide (5-10 Microns) was dispersed in water basedformulations to form a high viscous dispersion. The liquid dispersionthus obtained was precisely dropped in between two films through amotorized valve controlled slot nozzle in such a manner that a marginwas available at the end of the webs, so as not to allow the dispersionto ooze out from the sides. In this case warm water at around 40° C. wasused to deliver the dispersion to between two Cold WSF webs.

The properties of the ferric oxide incorporated films were:

GSM of Iron Oxide Loaded WSF=73 GSM (±½ Gm)

Thickness of Iron Oxide Loaded WSF=55 micronsGSM of reference WSF=58 GSM (±1 gm)

Weight of Iron Oxide Entrapping=15 GSM

Tensile Strength of Entrapped film (kg/cm²) Dir-I = 325.87 TestMethod—ASTM D-883 Dir-II = 327.77 Test Method—ASTM D-883 Young Modulus(kg/mm²) Dir-I = 7.18 Test Method—ASTM D-882 Dir-II = 8.26 TestMethod—ASTM D-882 Elongation (%) (kg/cm²) Dir-I = 341.9 Test Method—ASTMD-882 Dir-II = 324.27 Test Method—ASTM D-882 Puncture Resistance (Ozs.Inches/Tear Inch) = 600 Test Method—IS-1060 Dissolution in seconds = 37secs at 60 C. Breaking of the film = 19 secs at 60 C.

As illustrated in the earlier examples the material embedded films havefavorable film properties and can be used for diverse application. Thisapplication provides possibilities of embedding environmentallysensitive materials, wastes and toxic materials of diverse shapes, sizesand reactivities within an appropriate WSF Matrix in precise quantitiesfor storage, transportation or disposal. This method may also be used toembed powdered or granular materials of any shapes or sizes such aspesticides, solid deodorants, disinfectants, uncoated enzymes, toxicproducts etc. which are to be delivered to their point ofapplication/action or storage.

These applications also clearly demonstrate the wide number of productand process options using the methods disclosed in this invention.

We claim:
 1. A water soluble film (WSF) system comprising a watersoluble film having at least one active material embedded/entrapped insaid film at a selective concentration and depths/dispositions in saidfilm such that the said active material thus embedded/entrapped in saidfilm is delivered at preselected desired quantities.
 2. The WSF systemas claimed in claim 1 wherein said embedded/entrapped materials areselected active materials.
 3. The WSF system as claimed in claim 2wherein said active materials are selected from detergents, enzymes,softeners, perfumes, pesticides, fungicides, active ingredients, dyes,pigments, hazardous chemicals, active agents for cleaning laundry,dishes, floorings, walls, furniture, and combinations thereof embeddedin the WSF for delivering in precise and desired quantities.
 4. The WSFsystem as claimed in claim 1 wherein said water soluble film comprisesmultilayered film.
 5. The WSF system as claimed in claim 1 wherein thewater soluble film is made of a material that dissolves in the presenceof water and wherein the film is formed by providing a formulation for awater soluble film comprising said at least one active material andwherein a solution of the formulation is cast on an elongate liner toform said water soluble film on said liner with said at least one activematerial physically incorporated in the water soluble film such that theactive material is embedded in the water soluble film of the WSF system.6. The water soluble film system as claimed in claim 5 wherein said atleast one active material is selected from the group consisting ofdetergents, enzymes, softeners, perfumes, pesticides, fungicides, activeingredients, dyes, pigments, hazardous chemicals, active agents forcleaning laundry, dishes, floorings, and walls, and combinationsthereof.
 7. The water soluble film system as claimed in claim 5 whereinthe liner is a paper, film, foil or fabric, and the film liner materialis preferably selected from the group comprising plain, embossed,metallized, gloss, matte, extrusion coated laminated or release coated.8. The water soluble film system as claimed in claim 7 wherein the lineris a polyester film.
 9. The water soluble film system as claimed inclaim 5 wherein the film is of about 2 microns to about 500 micronsthick.
 10. The water soluble film system as claimed in claim 5 whereinthe film is about 10 microns to about 300 microns thick,
 11. The watersoluble film system as claimed in claim 5 wherein the film is about 12microns to about 250 microns thick.
 12. A product/package comprising theWSF system as claimed in claim 1 wherein said water soluble film and theat least one active material are selectively embedded or entrapped inthe water soluble film such that the at least one active material isprotected from environmental factors until the product/package is used.13. The product/package as claimed in claim 12 comprising a carrierliner adapted to be at least partially removed before use for dispensingat least some of said embedded/entrapped active materials from said WSF.14. A process for the manufacture of a water soluble film with at leastone embedded active material, the method comprising the steps of: i)taking up an elongate liner from a liner source; ii) providing aformulation for the water soluble film, the formulation comprising atleast one active material; the at least one active material beingselected from the group consisting of detergents, enzymes, softeners,perfumes, pesticides, fungicides, active ingredients, dyes, pigments,hazardous chemicals, active agents for cleaning laundry, dishes,floorings, and walls, and combinations thereof; iii) casting a solutionof the formulation with said at least one active material from step (ii)on the elongate liner to form an elongate water soluble film on saidelongate liner with said at least one active material physicallyincorporated in the water soluble film such that the active material isembedded in the water soluble film; iv) drying the cast water solublefilm with said at least one active material embedded and physicallyincorporated in said water soluble film on said elongate liner.
 15. Theprocess according to claim 14 wherein the liner is a polyester filmliner.
 16. The process according to claim 14 further comprisingdetaching the cast water soluble film from step (iv) from the liner ofstep (i).
 17. The process according to claim 14 comprising a furtherstep of casting a solution of a formulation for at least one furtherwater soluble film on the embedded water soluble film from step (iv) ata subsequent casting head to form a multi-layer water soluble film, anddrying the multi-layer water soluble film to produce a multi-layer watersoluble substrate.
 18. The process according to claim 17 wherein said atleast one active material is an at least one first active material, saidprocess further comprising providing at least one second active materialin the formulation for casting said at least one further water solublefilm; wherein said at least one second active material is the same as,or different from, the at least one second active material.
 19. Theprocess according to claim 17, wherein the multi-layer water solublefilm comprises combinations of water soluble films which dissolve atdifferent temperatures in any desired sequence.
 20. The processaccording to claim 14 wherein raw materials for the water soluble filmare selected from the group consisting of polyvinyl alcohol copolymerionomers, polyvinyl alcohol homopolymer, non-ionomeric polyvinyl alcoholpolymer, polymethacrylate, polyvinyl alcohol, polyacrylamide,polymethacrylamide, polyacrylic acid, and polymethacrylic acid or thegroup consisting of polyethylene glycols, polyvinylpyrrolidone,proteinaceous binders, gelatin, modified gelatins, phthaloyl gelatin,polysaccharides, starch, gum Arabic and dextrin, water soluble cellulosederivatives, and combinations thereof.